Retire modbus module

Author: PatAltimore

articles/iot-edge/.openpublishing.redirection.iot-edge.json

@@ -349,6 +349,11 @@
             "source_path_from_root": "/articles/iot-edge/how-to-continuous-integration-continuous-deployment-classic.md",
             "redirect_url": "/previous-versions/azure/iot-edge/how-to-continuous-integration-continuous-deployment-classic",
             "redirect_document_id": false
+        },
+        {
+            "source_path_from_root": "/articles/iot-edge/deploy-modbus-gateway.md",
+            "redirect_url": "/azure/iot-edge/how-to-create-transparent-gateway",
+            "redirect_document_id": false
         }
     ]
 }